1. Field of the Invention
The invention relates generally to physical exercise devices for human beings to maintain athletic proficiency, and more particularly to exercising devices to be used by snow skiers.
2. Description of the Prior Art
It is well known that snow skiing requires the use of certain disciplined motions and muscles upon which other athletic endeavors do not significantly rely. Snow skiing requires rapid and alternating shifts of weight between right and left feet as well as coordinated twisting and turning motions. In order to become proficient, muscular control and muscle tone in the legs, thighs, and ankles must be achieved. Professional and amateur skiers alike, because of the nature of the sport, have to travel long distances in order to obtain access to ski slopes, and once arrived, the actual amount of time spent on the slopes is small. Thus, the opportunity on the ski slopes for exercising critical maneuvers and obtaining strength in critical muscles is limited.
There have been attempts within the prior art to develop devices particularly suited to enhancing the specialized motions required for skiing and building muscle tone. U.S. Pat. No. 4,074,903 issued to Diez de Aux discloses an apparatus for simulating skiing down a slope. A slide or movie projector displays typical skiing terrain and a specially adapted platform introduces to skier to the accelerations that would be experienced when actually skiing over the terrain as projected. The cost of building the device as described by Diez de Aux is prohibitive to most amateur and probably to most professional skiers as well. The electromechanical apparatus to impart motion to the skier correlated to the projection system is both complex and costly. Moreover, the space required to practice the invention is significant and, the device is hardly portable.
U.S. Pat. No. 3,787,047 issued to Brawn discloses another device for ski training and muscular exercise. The apparatus is comprised of a flat board structure supported by three rolling bearing elements disposed in an isosceles triangle supporting the flat base from below. When the user stands upon the apparatus and unweights one foot in favor of the other, there is a tendency for the board to tip. It is this tipping motion, appropriately limited by the geometry of the board, which provides the exercise and training. The Brawn apparatus, while relatively inexpensive and portable, is limited in the motions that the apparatus can impart to the skier. That is, the platform can only tip or move in a predetermined arc defined by the location of the three rolling bearing means. Moreover, the Brawn apparatus does not exert any vertical forces or accelerations as are normally experienced traveling over undulating terrain.
Another ski exercising and training device is disclosed in U.S. Pat. Nos. 3,565,424 and 3,752,474 issued to Macabet et al. The devices disclosed in these patents are essentially constructed from both elastic and inelastic cables attached through pulleys to the user's body on the one hand and to an anchor support on the other hand. The user essentially exerts forces against his or her own body by movement of the user's arms and legs connected together through the pulley system of the apparatus which in turn is connected to an immovable anchor. Particularly adapted to skiers, Macabet et al describes an embodiment using clogs attached to the skier's feet permitting the skier or user of the apparatus to sway his or her legs in a lateral motion constrained by the cables of the system thereby providing resistance to said lateral motion. The Macabet apparatus suffers from various practical defects. For example, it must be anchored to an immovable object in order for it to be used; considerable floor space is required; and the clogs, hand pulleys and various components of the apparatus are cumbersome and relatively costly to manufacture. Moreover, with the Macabet apparatus the motions imparted to the skier are not similar to those actually encountered upon a ski slope. As the clogs suggested in the apparatus only permit lateral swaying of the user's legs, the motion is not indicative of the nearly 360.degree. tipping and turning associated with actual skiing.
Devices generally for exercising the human body are old in the art. U.S. Pat. Nos. 650,656 and 1,618,273 issued to Raabe and Davidson, respectively, disclose exercising devices utilizing a harness arrangement attached to the user's body. While no doubt effective in stimulating cardiovascular functions, these devices are not suited to enhance the particular muscles needed for skiing. U.S. Pat. Nos. 393,265 and 1,623,670 issued to Rice and Frankenfeld, respectively, disclose a different type of exercising apparatus from the Raabe and Davidson patents. The Rice and Frankenfeld apparatuses do not attach to the human body, but rather the user stands upon the apparatus and exerts forces against it. In the Rice apparatus the platform upon which the user stands is attached to two pairs of spring bars which permit the platform to tilt when the user exerts forces upon handles attached to outriggers. In the Frankenfeld apparatus the user simply stands upon a platform and exerts forces against said platform through elastic cords. As is true with the other references discussed above, none of these devices provide a motion which effectively simulates the rocking, tipping and swivel actions required in skiing.